import { FORMAT_DEFAULT } from '../../constant';
export default (function (o, c, d) {
  // locale needed later
  var proto = c.prototype;
  var oldFormat = proto.format;

  d.en.ordinal = function (number) {
    var s = ['th', 'st', 'nd', 'rd'];
    var v = number % 100;
    return '[' + number + (s[(v - 20) % 10] || s[v] || s[0]) + ']';
  }; // extend en locale here

  proto.format = function (formatStr) {
    var _this = this;

    var locale = this.$locale();

    if (!this.isValid()) {
      return oldFormat.bind(this)(formatStr);
    }

    var utils = this.$utils();
    var str = formatStr || FORMAT_DEFAULT;
    var result = str.replace(
      /\[([^\]]+)]|Q|wo|ww|w|WW|W|zzz|z|gggg|GGGG|Do|X|x|k{1,2}|S/g,
      function (match) {
        switch (match) {
          case 'Q':
            return Math.ceil((_this.$M + 1) / 3);

          case 'Do':
            return locale.ordinal(_this.$D);

          case 'gggg':
            return _this.weekYear();

          case 'GGGG':
            return _this.isoWeekYear();

          case 'wo':
            return locale.ordinal(_this.week(), 'W');
          // W for week

          case 'w':
          case 'ww':
            return utils.s(_this.week(), match === 'w' ? 1 : 2, '0');

          case 'W':
          case 'WW':
            return utils.s(_this.isoWeek(), match === 'W' ? 1 : 2, '0');

          case 'k':
          case 'kk':
            return utils.s(
              String(_this.$H === 0 ? 24 : _this.$H),
              match === 'k' ? 1 : 2,
              '0'
            );

          case 'X':
            return Math.floor(_this.$d.getTime() / 1000);

          case 'x':
            return _this.$d.getTime();

          case 'z':
            return '[' + _this.offsetName() + ']';

          case 'zzz':
            return '[' + _this.offsetName('long') + ']';

          default:
            return match;
        }
      }
    );
    return oldFormat.bind(this)(result);
  };
});
